Science and Whisky! Does caramel coloring make a difference?

Single malt Scotch whisky comes in a beautiful range of colors: warm goldenrod, deep russet, bright dandelion. Thanks to the variety of casks used to age whisky, the length of time the spirit spends in them, and the various mixtures of different casks to create the final product, the palette available to Scotch drinkers makes a lovely sight. Check out this color bar with its whimsical, somewhat confusing names (I never realized there was a difference between yellow gold and old gold).

But did you know that some Scotch whisky contains an additive coloring called E150a? Many whisky lovers believe this so-called “caramel coloring” impacts the flavor of the spirit, but producers who use it insist it does not. A few months ago, in an effort to provide some evidence one way or another, Johanne McInnis, the Whisky Lassie and one of half of The Perfect Whisky Match, planned and executed a blind tasting of a single whisky expression with and without E150a.

That wee tiny phial contains pure E150a.

The instructions dictated the participants carry out the test blind—so I enlisted the help of my husband to pour and keep track of whether my guesses were right or wrong. After I put on my blindfold (really!), he poured 10 ml of each sample into a Glencairn glass and placed them in either hand. I also had a glass of plain water in the middle. I nosed each one and made my guess three times in a row with a five minute wait in between each nose. (And Sunjay mixed up—or not—the glasses between each round too.) Finally, I tasted each without water, making a guess based taste and trying not to let my impressions of the nose get in the way.

I repeated this process three more times over the next few days at different times of day. Sunjay patiently recorded my guesses and only revealed them when the final drop had been drunk. I did not open the tiny bottle of E150a until after the experiment was over, so as not to prejudice my guesses.

My first test took place in the mid-afternoon. When I initially nosed the two whiskies, I immediately smelled a difference. One whisky was distinctly sweet and sugary on the nose, while the other had more floral character. I had no idea what kind of qualities the E150a would impart: would it add something extra, or take something away? With no clue, I decided the sweeter-smelling one was more suspect. I generated some kind of reasoning in my head involving sherried whiskies being both dark and sweet, but it didn’t really make sense even to me. I honestly couldn’t decide which one was meant to have the coloring added: not knowing the smell or taste of E150a, it was a true blind guess. That the two whiskies were distinct and different, however, was obvious.

I nosed three times and detected that difference each time, selecting the sweeter-smelling one as having added color. When, after three nosings, I tasted each, I found a difference there, too. This time, however, the sweet-smelling one tasted more like whisky to me. So I chose the other whisky as the one with added color. Either way, I’m half-right, right?

I covered the glasses and left them for a couple of hours and then returned. This time the difference in smell was still there but more subtle. Slight oxidation had regulated the differences between the two so that they were closer in scent. One still stood out as smelling more like brown sugar (slightly reduced by this time), however, and I stuck by my original supposition and designated it the “colored” whisky another three times.

When it came to tasting, however, I actually became stymied. By this point the whiskies were so similar (and a bit too warm) that they were virtually indistinguishable. Each of them had a slight sweetness on the nose and on the palate, with sweetness, some spiciness, and oak at the finish. One of them did taste a bit duller than the other; or perhaps the other was just brighter and more vivid, so I chose the flatter one as the one with coloring.

The next day, I repeated the process. At this point, I began second-guessing everything I knew about how whisky smells and tastes. If I didn’t know one of the samples had coloring added, I’d never guess that either of them were altered in any way: they both smelled and tasted “like whisky” to me. But is this because my knowledge of whisky is tainted by drinking and “knowing” whiskies that use coloring? Surely that influences my perceptions of what “tastes” and “smells” like whisky. In any case, I took a truly blind guess for the third time.

A couple of days later, I did the fourth and final test. At this point I just gave up on trying to use any logic or method and just chose one. When the last drop had been swallowed, my results were revealed:

Tasting 1: Noses 1-3 WRONG; Palate CORRECT

Tasting 2: Nose 1 CORRECT, Nose 2 WRONG, Nose 3 CORRECT, Palate WRONG

Tasting 3: Noses 1-3 CORRECT, Palate CORRECT

Tasting 4: Noses 1-3 CORRECT, Palate WRONG

I was surprised. I had really convinced myself that the first-round nosing was totally correct, but no. At least the other nosings (with one exception) were consistent. My tasting was 50/50, which doesn’t surprise me as I really, truly didn’t know what to be looking for. Not knowing what the additive tasted or smelled like ahead of time, I was taking a stab in the dark, assessing each dram to decide which one “tasted more like whisky.” It’s interesting to see that this worked out for me in the initial round, when I was still forming judgments about the process and the two whiskies, as well as in the third round, when I had spent a lot of time thinking about my perceptions of whisky and whether or not they could be trusted. I’m not surprised I got the final round wrong as I’d basically thrown in the towel at that point.

The problem with making my choice based on which dram was more whisky-esque is that my tasting experience has included both colored and additive-free whiskies. And most of the time, I haven’t known or paid attention to E150a presence. So my palate has, in some way, been “tainted” by my tasting of colored whiskies as on par with (or at least undistinguished from) non-colored whiskies. They have all been lumped into the “tastes like whisky” category.

And this impacted my ability to judge the “whisky-ness” of each dram. The truth is, they both tasted like whisky to me. Heck, they both smelled like whisky too, but it was easier to detect what I thought was a hint of something “fake” on the nose than on the tongue. The sweetness I associated with the E150a stood out like a red flag every time I smelled it (or thought I did). But the two tastes—that was much harder. One whisky (which ended up being the E150a) had a stronger spicy character and what seemed to me a more rounded finish. The other seemed less vivid with a less satisfying finish—some of the time. Both whiskies, after oxidizing a bit, tasted even more similar, further complicating my perceptions.

This whole thing turned my preconceptions about whisky on their head. What should whisky smell like? I found the nose on the E150a whisky rather pleasant, just as the nose on the non-colored whisky was, too. What should whisky taste like? There is no doubt in my mind that the additive changes the flavor of the spirit, although this seems to lessen when the spirit breathes a little. The E150a whisky provided, in my opinion, a more rounded finish albeit a less nuanced palate overall. Would it be wrong to prefer the additive whisky over the “pure” one?

If making the argument from taste, my guess is that both colored and additive-free whiskies would have their fans in a widespread blind tasting. Should consumers know when E150a has been added? Absolutely, and in many cases, folks can guess (does the bottle say no colouring added? If not, buyer beware). Since I personally have a bias against additives and things like that in all the food and drink I consume, I would be more likely to purchase non-colored whiskies, especially single malts, an effort to maintain the purity of what I consume. But if I already knew and loved a standard bottling like, say, Glenfiddich 12, and I found out it contained E150a (which it does), would I stop drinking it? No way. I drink what I like.

Of course, E150a isn’t added for taste. It’s used to ensure consistent color across all bottlings of an expression. Visual cues, like labels, impact our perceptions of quality and enjoyment, and producers know this. If your Glenfiddich 12 appeared deep gold one year and pale yellow the next, you’d wonder if they were altering the product somehow (and you might find the pale yellow one less satisfying). Keeping the product visually consistent signals that it remains consistent in nose and taste, too. Visual consistency remains an important issue in countries where there is less regulation and oversight of food and beverages, and where consumers might not feel confident about the quality of a product whose appearance varies. (Then again, it cuts both ways: producers in such countries can more easily use additives to achieve visual consistency, opening the door to some horrible realities.)

In the end, I suppose I’m still on the fence about E150a in my whisky. I’m certainly going to be inspecting all the bottles I buy from now on, and, as I wrote above, I’ll likely privilege those without any additives. But I respect the decision of producers to use E150a to create visually-consistent whiskies. Frankly, I’m more anxious that chill-filtering will affect the smell and taste of a whisky. But who can say for certain, unless we do some more research…